It was a tale of contrasting fortunes for the FTSE 100's two biggest
independent explorers, as Cairn Energy came up with its sixth dry well in
Greenland and Tullow Oil made a new discovery in Ghana.

Cairn's share price dropped a further 5pc to 281.62p, after it did not find oil in the third well it has drilled this year.

The company did not find any success last year either and has only two more wells to go before the freezing Arctic winter weather stops work for the rest of 2011.‎

Cairn has placed all its hopes on finding oil off Greenland, after selling most of its Indian assets to Vedanta for $9bn (£5.5bn). It has almost completed this deal after more than a year of delays. Some money will be returned to shareholders and the rest will be used to fund its drilling programme.

It has pledged to spend $600m this year drilling off Greenland, which it hopes will be the world's big new oil frontier. The company has found traces of oil in previous Greenland wells but not enough to make them worth developing.

Meanwhile, FTSE 100 rival Tullow Oil made an oil discovery in Ghana, where it started producing for the first time earlier this year. Tullow, which recently also struck oil off French Guiana, owns almost half the Enyenra discovery.

However, its share price dropped slightly to £13.20. Investors are waiting nervously to see whether the company can manage to strike a good deal with the Ugandan government over the $10bn development and infrastructure for its giant Lake Albert field with two partners - CNOOC and Total.

Approval was meant to be given for CNOOC and Total's participation earlier this month, but the parties are still wrangling over a "stabilisation clause". This clause, opposed by the Ugandan government, would make the oil companies more protected from political instability, such as tax changes.